Sterility-maintaining connection system for medical systems and use thereof

ABSTRACT

The invention describes a connection system comprising at least a male connecting element and a female connecting element which can be connected to each other, as well as the male connecting element and the female connecting element. The location of contact of the two connecting elements is preferably provided with a disinfecting adhesive so that an aseptic or sterile connection can be established. Therein both connecting elements have predetermined breaking points which in the connected state are arranged one above the other so that only one breaking point within the tube is obtained via which an aseptic fluid guidance through two tubes from one sterile system to another sterile system can be carried out. Thereby a particularly simple and cost-saving connection is created which fulfills the highest sterility requirements.  
     Furthermore, also the use of such a connection system is described.

[0001] The invention relates to a sterile and/or aseptic connection system and the use thereof in medical systems, especially in a set for cell separation for the sterile connection of further bags to an existing set. The invention relates in particular to two connecting elements which are connectable to each other in a sterile and/or aseptic manner, for transporting a fluid from one closed sterile bag into a second sterile bag.

[0002] In prior art there are known numerous connectors which, in part, also enable a sterile connection. Said connection systems have become necessary in order to avoid any contaminations during the transfer of liquids which have to be kept sterile. This is for instance required for this transfer of infusion solutions, dialysis solutions or blood or blood components. In the field of infusion technology, several transfer systems are known which usually consist of a septum and the pertinent needle. When transferring liquids for the entaral feeding, spikes are used which have a larger flow volume.

[0003] While the sterility of the spikes and cannulas in the infusion, i.e. the direct use of the solutions, usually is sufficient, an increased sterility requirement has to be fulfilled regarding the sterility of blood or blood components to be stored or regarding the transfer a dialysis into the peritoneum in order to avoid a microbic contamination. Such solutions, on the one hand, provide an optimum culture medium for bacteria and a and, con the other hand, in most cases they also provide an optimum temperature environment. In case of a peritoneal solution, a germ could cause a peritonitis, i.e. an inflammation of the peritoneum, which can lead to irreparable damage. In the case of products to be stored, by ideal reproduction conditions the number of germs increases such that the immunological system is overstrained with a corresponding defense or resistance.

[0004] Therefore it is demanded and usual that for the transfer of blood from one closed system to a second system as well as for the transfer of solutions into the peritoneal cavity a sterile connection is used which provably cannot be contacted at its point of connection by the medical staff or by the patient himself or herself, not even inadvertently.

[0005] Therefore, in known sterile connectors the closing element itself, for instance the screw cap, is displaced inwardly and is protected against contact by a wrapping element drawn over the cap.

[0006] Contamination is also possible by air contact so that connection systems are also known which have an internal disinfecting means—for instance soaked little sponges—so that when the elements are assembled, a disinfectant like iodine PVP is set free and thereby a microbic contamination is prevented. But in such systems a part of the disinfectant passes into the tube connection. In view of this it has to be guaranteed that the disinfectant does not cause any damage or harm.

[0007] Furthermore it is known to establish the fluid connection only when the connection system has already been closed in a sterile manner. In WO 81/01105 there is shown a predetermined breaking point inside a tube which renders possible the flowing-through by breaking off the plastic pin. Said system, however, is produced with a fixed tube coupling and is sterilized thereafter, so that no connection is required.

[0008] In DE 29607437 U there is for instance described a medicotechnical connecting device with an internal threat the fluid connection of which is enabled by opening a break seal located in an inner cone axially spaced apart from the insertion end and therefore can only be penetrated by the outer cone of the counter connector.

[0009] A particularly quick and safe opening of the fluid path is realized by breaking off, as is for instance described in EP 0 555 927 A2. In said publication a connecting element is described which sealingly closes the end of a tube. A predetermined breaking line enables the breaking-off of the seal at the accurate position in order to open the outlet.

[0010] Also in WO 94/12224 there is shown a blood tube system which shows a clamp with a predetermined breaking point on a supply tube. By means of said clamp the tube can be alternatively only clamped off from the inlet section or it can be separated by breaking off at the predetermined breaking point,

[0011] It is already known from U.S. Pat. No. 4,007,738 to provide an in-lying predetermined breaking point for a connecting element, with an end part of a connecting tube being broken off at a predetermined breaking point located within a small connecting tube This broken-off part can, however, result in an unwanted plugging of the line in the solution proposed there.

[0012] A connection system is known from U.S. Pat. No. 5,743,892 where a reservoir with disinfectant means is already provided which serves to disinfect the connection point when the female and male connecting elements are put together.

[0013] It is an object of the present invention to develop a connection system which satisfies high sterility requirements, but can nevertheless be produced in a simple and cost-saving manner. Said object is solved by the features mentioned in claim 1.

[0014] The inventive connection consists of two parts, namely a male connecting element and a female connecting element which can be inserted into one another so as to accurately fit together.

[0015] The connection is to be made for instance by a screw thread or via snap-in elements. Preferably the two connecting elements, however, are joined with each other by means of an adhesive in a preferred embodiment, the connecting elements are irreversibly joined to one another in order to achieve additional security.

[0016] A marking, e.g. a stop or a catch, at the connecting elements allows to determine whether a positive locking of the connection has been obtained or not.

[0017] Therein both parts each have a predetermined breaking point which, after the positive connection, lie as close to each other as possible. Even when tolerances are possible, the predetermined breaking points should preferably be arranged directly one above the other. Said position guarantees that when the predetermined breaking points are broken a common breaking position is obtained at which the fluid to be transferred can exit.

[0018] The contact portion of the connection system is provided with an adhesive which has a disinfecting effect. Thereby a thread or another connection difficult to be established can be avoided For the connection by means of an adhesive there are principally two possibilities.

[0019] On the one hand, the adhesive can be disposed on the male connecting element. In this case the surface of the male connecting element is for instance dipped into a liquid adhesive or the adhesive is applied so that during the connection also a complete wetting of the point of contact is obtained. When the connector is delivered in an already wetted state, a protective covering is provided.

[0020] On the other hand, the adhesive can also be provided in the female connecting element. In this case the adhesive is preferably enclosed in a small storage container, for instance in a thin polymer cover or in a plurality of containers such as beads or microbeads within the connecting element. It is therefore possible to use a one- or multi-component adhesive encapsulated in small spheres.

[0021] When the female and male connecting elements are assembled, the adhesive reservoir will burst, and the adhesive will be uniformly spread over the entire location through the press fit. But it is also possible that the adhesive is spread over the inside and that the connector is closed in a sterile manner against the outside by means of a protective cap, a prtective covering or by a glued-on pierceable protective membrane or a septum. The protective membrane can here be attached both to the female and the male connecting elements.

[0022] In a preferred embodiment, the adhesive itself has a disinfecting effect or a disinfecting means is added to the adhesive together with or in other beads. During assembly or a closing forced by snapping-in or turning, said beads or small spheres containing the adhesive and/or the disinfectant means burst and mix in order to connect the surfaces to one another and/or to disinfect,

[0023] Furthermore it is advantageous that the adhesive is quick hardening so that the connection will not be disconnected again during the use thereof. In this respect cyanoacrylate is mentioned as an example, as it has such an effect. But it is also possible that the adhesive itself is not disinfecting or that the positive locking is obtained via a thread or locking means. Then, for guaranteeing the sterility, additionally a disinfectant should be inserted between the contact surfaces of the male and the female connecting elements. When both connecting elements have been assembled, the adhesive spreads over the entire contact location and hardens or cures within a few seconds.

[0024] Then the connection is bent, whereby a break of the connected connecting elements at the predetermined breaking point is obtained, The broken-off section has to be designed such that it gets stuck in the tube but nevertheless does not form a stopper for the fluid flowing through the tube. This is obtained by the fact that the breaking point is provided not too far away at the end of the connection system, as otherwise the fragment could be too small and could be transported further on in the tube. But it may also not be provided too far away at the broad side of the connection system, as otherwise the risk of a jamming is given. Due to said reasons the predetermined breaking points are advantageously chosen such that they are provided approximately in the middle of a connection system having a long and thin structure.

[0025] As already mentioned, the predetermined breaking points of the male and female connecting elements are located one above the other in the assembled state, so that in case of a break no adhesive or disinfectant will enter the inside of the connection system. It is self-evident that tie breaking point is located inside the tube ends to be connected so that the tube itself provides the sealing against the outside.

[0026] The connector arrangement in accordance with the invention is used, for example, in bag and tube arrangements in which a connection has to be made in a sterile/aseptic way. These bag systems can be blood bag systems which often also contain a filter such as a leukocyte depletion filter. Depending on the application of these bag systems, the addition of a filter is necessary or not so that the filter, individual bags or tube pieces can be assembled freely in any way to form a complete bag systems.

[0027] It is thus naturally also possible for two or a plurality of connections to be formed at one connector system as is illustrated in the description of the figures.

[0028] Hence, by the inventive connection arrangement the contamination risk can be easily and safely avoided. This applies, on the one hand, to the medium flowing in the inside, e.g. blood, as neither adhesive or disinfectant can get into the blood, nor germs which would render the storage and the use of conserved blood impossible. And, on the other hand, by said safe and permanent glue connection also no blood can get into the environment, so that also thereby a contamination by for instances viruses cannot be transported any further.

[0029] Preferably the connecting elements are made of plastic, e.g. polycarbonate, acrylonitrile butadiene styroles, polyethylenes, polypropylenes, polystyroles, polymethyl methacrylates, polysulphones or methyl methacrylate butadiene styroles or methyl methacrylate acrylonitrile butadiene styroles which should be compatible with the tube material coming into contact with them, with the adhesive, as well as with the media flowing therethrough. In the case of blood or blood components there is suitable a PVC tube or also a polyolefine tube.

[0030] Advantageously, protective caps are provided for the male and female connecting elements, said protective caps being connectable to the respective elements and keeping these sterile and protecting them against damage until they are assembled.

[0031] In the following a preferred embodiment of the connection system is described by way of the description of the figures.

[0032]FIG. 1 shows the connection system in a disconnected state;

[0033]FIG. 2 shows the connection system in a connected state;

[0034]FIG. 3 shows an embodiment in which the adhesive and/or the disinfectant means is present in a plurality of micro-spheres;

[0035]FIG. 4 shows the connection system with two beads;

[0036]FIG. 5 shows a membrane inside the connection system as a termination;

[0037]FIG. 6 shows different forms of the connection system in intersection;

[0038]FIGS. 7a, b and c show multi-connection systems; a/b without and c with filters;

[0039]FIGS. 8, 8a show a side view and a section through the male part of the connection system which is connected to a protective cap; and

[0040]FIGS. 9, 9a show a side view and a section through the female part of the connection system to which a protective cap is connected.

[0041] In FIG. 1 there is shown a connection system which serves for the connection of two tube sections 3, 4, wherein the female and the male connecting element 1, 2 are provided separately. The first tube section 3 receives one part of the female connecting element 1, so that the tip thereof comes to lie inside the tube. On the other hand, in the inner section 5 of the tip there is a storage of an aseptic adhesive 6.

[0042] The female connecting element has a predetermined breaking point 8 which results from a material saving extending circularly around the connector. In the present case the material saving is provided in the form of a circular notch at the outer section 10 so that the internal surface 9 has a smooth surface.

[0043] The male connecting element 2 is irreversibly fixed at its connection end to a tube end 4 so that the tip of the connector is freely visible. Also the male connecting element has a predetermined breaking point 7 situated, in contrast to its counterpart, in the inner section 12 so that the outer surface 11 is also smooth. The position of the predetermined breaking point is only represented in rough outlines in the present figure. As already described in the text, it has to be guaranteed that the broken end piece is wedged in the tube without preventing the flow therethrough.

[0044] In the connected state—as shown in FIG. 2—the predetermined breaking points come to lie one above the other and thereby result in a single common predetermined breaking point. Due to the press fit, the adhesive has been uniformly spread over the surfaces 9 and 11 and positively connects the connecting elements. Advantageously, both connecting elements 1, 2 have a stop 13, 14 which indicates to the user whether the two connecting elements have been positively pressed on one another or not. In the closed state there may no longer be seen any gap between the stop 13 of the female connecting element and the stop 14 of the male connecting element. Also a canting thereof is exactly visible.

[0045]FIG. 3 shows the connector system with a plurality of small beads 15 which each contain either adhesive or disinfectant means.

[0046]FIG. 4 shows only two reservoirs 16 and 17 which should each contain one component of a two-component adhesive. The embodiments are, however, naturally not restricted to two components.

[0047]FIG. 5 discloses a membrane 18 or a septum inside the female connection system which can be penetrated with the aid of the male part and thereby the enclosed means released.

[0048]FIG. 6 shows the geometric designs of the connection system with a) being circular, b) triangular, c) quadrangular and d) elliptic.

[0049] FIGS. 7 each show the multi-connections in schematic form. FIG. 7a shows a multi-connector 19 at the male part and at a female part 20, whereas in 7 b the multi-connector 19 is associated with individual other female counterparts. FIG. 7c has had filters 21 added, preferably for the elimination of leukocytes.

[0050]FIGS. 8 and 8a show the male connecting element 2 in accordance with the previously described design, to which a protective cap 22 is connected via the corresponding screw connection 23.

[0051] In a similar manner, the female connecting element 1, which also corresponds to the previously described design, is connected to a protective cap 24 in FIGS. 9 and 9a, The protective cap 24 corresponds in its shape to the male connecting element 1. The protective caps 23 and 24 have wing-like protrusions, as illustrated in FIGS. 8 and 9, which simplify handling of the protective caps in releasing and tightening.

[0052] The protective caps 22 and 24 serve to protect the male connecting element 2 or female connecting element 1 and have threads 23 and 25 respectively in order to be reliably connected to the male or female connecting elements respectively so that a contact of the connecting elements to the environment is reliably prevented up to the release from the protective caps 22 and 24. The protective caps 22 and 24 further provide protection against externally arising forces or pressures arising internally in the line system. Normally, the protective caps 22 and 24 are only removed directly before the assembly of the female and the male connecting elements by the operator. 

1. A connection system for the connection of in particular two or more sterile systems, comprising at least a male connecting element (2) forming a closed end of a sterile, fluid-containing system and at least a female connecting element (1) forming the closed end of a second sterile, fluid-containing system which can be aseptically connected to one another, characterized in that both connecting elements (1, 2) each have a predetermined breaking point (7, 8) being arranged one above the other when the two connecting elements (1, 2) are assembled so that they form a common predetermined breaking point and can be broken off together, with the predetermined breaking point being located inside the fluid-containing system.
 2. A connection system according to claim 1 , characterized in that the two connecting elements (1, 2) can be connected to each other in a positively locking manner.
 3. A connection system according to one or more of the preceding claims, characterized in that the connecting elements (1, 2) can be connected to each other by means of a screw thread.
 4. A connection system according to one or more of the preceding claims, characterized in that the connecting elements (1, 2) can be connected to each other by means of a snap-in connection.
 5. A connection system according to one or more of the preceding claims, characterized in that the connecting elements (1, 2) can be connected to each other by means of an adhesive connection.
 6. A connection system according to one or more of the preceding claims, characterized in that the adhesive connection is a quick-hardening adhesive.
 7. A connection system according to one or more of the preceding claims, characterized in that a disinfectant is provided between the contacting contact surfaces (9, 11) of the connecting elements (1, 2).
 8. A connection system according to the preceding claim, characterized in that the disinfectant has bonding properties.
 9. A connection system according to the preceding claim, characterized in that the disinfectant is a quick-hardening adhesive.
 10. A connection system according to one or more of the preceding claims, characterized in that cyanoacrylate is provided for connecting the two connecting elements (1, 2).
 11. A connection system according to one or more of the preceding claims, characterized by a protective cap (22) the external contour of which is matched to the male connecting element.
 12. A connection system according to one or more of the preceding claims, characterized by a protective cap (22) in the form of a male connecting element that is connectable to the female connecting element (1) for the protection thereof.
 13. A female connecting element (1) which forms the closed end of a fluid-containing system, for the connection with a male connecting element (2) which forms the end of a second fluid-containing system, characterized in that the female connecting element (1) has a predetermined breaking point (8).
 14. A male connecting element (2) which forms the closed end of a fluid-containing system, for the connection with a female connecting element (1) which forms the end of a fluid-containing system, characterized in that the male connecting element (2) has a predetermined breaking point (7).
 15. Use of a connection system according to claim 1 for the sterile transfer of fluid within a bag system, comprising at least two bags and a tube system.
 16. Use of a connection system according to claim 15 for the sterile transfer of biological or medical fluids in a bag system having at least two bags and a tube system.
 17. Use of a connection system according to claim 15 and 16 in a sterile blood bag system for the sterile transfer of blood or blood components.
 18. Use of a connection system according to claims 15 to 17 in a bag and tube system having at least one filter element for the sterile transfer of blood or blood components.
 19. Use of a connection system according to claim 15 in a bag system for the sterile transfer of infusion solutions or dialysis solutions. 